The present invention relates to a composition containing, as a main component, titanium dioxide effective for enhancing deodorization, decontamination, removal of germ and cleaning properties of dental products such as a crown, a denture, an orthodontia bed, a mouthpiece or the like made of acrylic resin composition. More particularly, the present invention relates to a compounding agent essentially consisting of a composition containing, as a main component, titanium dioxide suitable for enhancing deodorization, decontamination, removal of germ and cleaning properties of dental products made of kneaded acrylic resin composition, a coating agent essentially consisting of a composition containing, as a main component, titanium dioxide to be coated on a surface of a dental product in use for enhancing deodorization, decontamination, removal of germ and cleaning properties of the dental product, and a detergent essentially consisting of a composition containing, as a main component, titanium dioxide suitable for cleaning a dental product.
As a dental prosthesis such as a denture, an orthodontia bed used in general in a conventional dental treatment is contaminated by plaque gradually adhered thereto in a mouth, it is needed to daily wash the dental prosthesis by mechanical washing such as brushing or use of a denture detergent. Although the surface contamination of the denture can be removed by the mechanical washing or use of the denture detergent, removal of contaminant and coloring matter absorbed in the denture is difficult. For this reason, there has been proposed a method of coating a denture, an orthodontia bed, a denture repair material, a mouthpiece, etc. with a dental resin composition mixed with deodorant ingredients, decontamination ingredients or the like.
As a dental resin composition of this kind used in the coating treatment, proposed in Japanese Patent Laid-open Publication No. 5-32516 is a germicidal thermosetting resin composition mixed with fine particles of titania deposited therein with a metal for effecting photoelectrochemical sterilization function of titania. As a deodorant dental resin, proposed in Japanese Patent Laid-open Publication No. 10-273412 is a deodorant dental resin composition containing ester monomer of methacrylic acid, anatase-type titanium dioxide (TiO2) and polymerization initiator. With regard to the dental resin composition, it is reported that a dental material made of the dental resin composition has a resolution effective for deodorizing a foul odor and contaminants absorbed therein in a mouth under irradiation of light and that a foul odor unremoved in use of a conventional detergent can be removed when a denture made of the dental resin composition is washed under fluorescent light or sunbeam.
Although the germicidal thermosetting resin and the deodorant dental resin composition are utilized to effect activated photocatalysis of titanium dioxide, these dental resin compositions are decomposed due to activated photocatalysis of titanium dioxide, resulting in deterioration in strength and changes in color and quality. For this reason, the dental resin composition may not be used for a long period of time.
In addition, the following problems will occur in use of the dental acrylic resin material in a mouth due to a water-absorption property and an oil-absorption property of the material.
1) Unpleasant feel caused by permeation of odor
2) Spoil of beauty caused by adherence of coloring matter.
3) Adherence of tartar, residue of foods, etc.
4) Breeding of germs caused by impurities.
It is difficult to solve the problems by mere mixture of titanium dioxide with the foregoing dental resin material.
To solve the problems discussed above, a primary object of the present invention is to provide a dental resin material, a dental resin product, a compounding agent, a coating agent and a detergent capable of enhancing sterilization and deodorization properties caused by activated photocatalysis of titanium dioxide and of restraining decomposition, deterioration in strength and changes in color and quality of the dental resin material.
To attain the object, the inventors noticed the facts that apatite such as apatite hydroxide, calcium phosphate or the like has a restraint function of deterioration of the dental resin material and an absorption function of contaminants such as residue of foods and that sterilization and deodorization functions are effected by activated photo-catalysis of titanium dioxide. Based on the above observation, the inventors developed a composition effective for deodorization and decontamination of dental products, which contains apatite effective for restraining deterioration of the resin caused by titanium dioxide and for absorbing contaminants in use of the dental products in a mouth and titanium dioxide effective for sterilizing contaminants absorbed in the apatite and deodorizing foul odor matters by activated photocatalysis during washing of the dental products under irradiation of light.
According to the present invention, there are provided the following dental resin material, compounding agent, coating agent and detergent.
1) A dental resin material mixed with a composition containing, as a main component, titanium dioxide whose surface has been partly coated with apatite.
2) A dental resin product provided therein with a composition containing, as a main component, titanium dioxide whose surface has been partly coated with apatite.
3) A compounding agent containing, as a main component, titanium dioxide whose surface has been partly coated with apatite to be mixed with a dental resin material for use.
4) A coating agent containing, as a main component, titanium dioxide whose surface has been partly coated with apatite to be coated on the surface of a dental resin product in use.
5) A detergent containing, as a main component, titanium dioxide to be used for washing of a dental resin product.
6) A detergent containing, as a main component, titanium dioxide whose surface has been partly coated with apatite to be used for washing of a dental resin product.
7) A detergent of a dental resin product in the form of an aqueous solution in which an adjustment agent consisting of acid, peroxide, enzyme or a compound of these components is dispersed and mixed with titanium dioxide whose surface has been partly coated with apatite.
In actual practice of the present invention, it is desirable that anatase-, rutile-, brookite-type titanium dioxide or a mixture of these components is used as the titanium dioxide for the foregoing dental resin material, dental resin product, compounding agent, coating agent or detergent.
The apatite for partial coating of titanium dioxide is produced by immersing powdery titanium dioxide in an amount of a pseudo body fluid and stirring the immersed titanium dioxide approximately at the temperature as the human body temperature, i.e., at about 36xc2x0 C. In this instance, it is important that the apatite is deposited in the form of platy crystals of less than 2 mm in thickness to cover 0.001-10 wt. % of the surface of titanium dioxide.
In the production process of the dental resin material, an optimum result was obtained when a mixture amount of the titanium dioxide partly coated with the apatite is adjusted to 0.001-20 wt. %, desirably to 0.01-20 wt. % of the dental resin such as dental acryl resin or the like.
In the production process of the detergent, it is desirable that phosphoric acid, sodium pyrophosphric acid or hydrogen peroxide is used as the adjustment agent. In this instance, a desired result was obtained when the amount of phosphoric acid was adjusted to 0.001-100 wt. %, preferably to 0.01-10 wt. %, the amount of sodium pyrophosphoric acid is adjusted to 0.001-20 wt. %, preferably to 0.01-10 wt. % or the amount of hydrogen peroxide is adjusted to 0.1-36 wt. %, preferably to 2.0-7 wt. %.
The dental resin material of the present invention is most suitable for production of a crown, a denture, a mouthpiece or the like and is used in necessity as a tooth restoration material, a prosthesis material, a denture stabilizer, a model material, an orthodontia material or the like. The detergent of the present invention is most effective to decontaminate and deodorize the dental resin product when it is used to wash the resin product under irradiation of fluorescent lamp or sun beam thereby to clean the resin product without causing any change in quality and color.